Trouble with Inlay detail

[Toby Jutras]

I need some help getting better quality on my inlays. I’m finding that fragile parts like the tips of my stars are breaking, leaving a void in my inlay. 😞.


I’m using an Amana RC-1108 bit at 18,000RPM on Maple and have tried between 10-40 IPM cut speed.


When well supported, the cuts are awesome as shown in the walnut female part.


Any insights welcome.

[Grant Wilkinson]

I don't see any pic. How deep are you cutting the female?

[Toby Jutras]

sorry... here is the pic. Female is 0.2” deep.

88038543-67F4-42BE-881D-994B8C86FACE.jpg
D7768248-9673-4BEC-890A-F260191B7445.jpg
D3E50937-601D-411F-A137-8ADCEDB95962.jpg

[David Falkner]

Try the Amana 3-flute 60° bit, 1/4" and you'll probably get better and cleaner cuts than the one flute bit you're using.

David

[Bill George]

I was going to suggest a finer grain wood. That looks like white pine?

[Grant Wilkinson]

FWIW, the cuts on the male stars look like a dull bit to me. If my search engine returned good results, that bit uses a carbide insert. If you do a lot of these cuts, you may want to turn the insert to clean edge. All that said, I agree with David that a 3-flute 60° would likely do a better job.

[Toby Jutras]

I was going to suggest a finer grain wood. That looks like white pine?

Thanks, it is actually maple from my stock. I don't know whether it is soft or hard maple though...

[Toby Jutras]

Try the Amana 3-flute 60° bit, 1/4" and you'll probably get better and cleaner cuts than the one flute bit you're using.

David

Thanks for the recommendation - I'll order one today!

[David Falkner]

Be sure to follow up with us on how the new bit works for you. I began using that bit several months ago and it's a very clean cutting bit.

David

[Jim Becker]

I agree with the tooling change and be sure you're being gentle with the feed speed with those delicate points.

I will add that "sometimes" it's also the specific piece of wood. Stuff happens...

[Mark Bolton]

sorry... here is the pic. Female is 0.2” deep.

Welcome to the world of wood, and hard maple to boot. If you honestly want dead clean with as close to zero possibility of bad machining, you wont be able to use a standard Vcarve type toolpath or a profile toolpath and instead you'll need one that only leads in to each leg of the star in either a climb or conventional cut that leaves supported material. Those super fragile sharp tips will just pop off any other way and even with the most conservative cut strategy they may just pop off anyway.

Not sure how your going about this now but if your trying to machine the entire field of stars in the flag as one single vcarve inlay I would ditch that strategy and I would nest as many stars as possible in the smallest grouping possible (material yield) and I would machine the stars as individual stars which means you can toss the rejects and keep the sharp ones and cut them out on the band saw/scroll saw. You could much better than wasting an entire inlay of CNC machining because 6 tips broke off.

Hard Maple is a bear but honestly all those super sharp edges (needed) are a bear no matter what wood.

[Tony Leonard]

I've been using the Amana 1541 for my inlay for a few years. I've cut pretty much all of the domestic woods in very small detail and not had any issues. Are you using Vcarve? I did mess up once and used a setting that made several laps and that messed up my design a bit. Other than that, the method is pretty good, so I have to wonder about thar tool as others have. Hope it works out well for you. I have only bought one of the Spektra bits so far and it does cut very nice. I'll be interested to see how long it lasts or if I'll be able to tell.

[Mike Heidrick]

I use CMT Laser 3 flute 60 degree bit with amazing success. I like teh 1/2" shank option. Might be a cheaper than an Amana option.

858.501.11 is model number

MFG details - https://www.cmtorangetools.com/na-en...ter-bits-60deg

[Jim Becker]

I use Amana's insert vee-bits for anything important.